Remote engine start and stop system

ABSTRACT

A remote engine start and stop system for remotely starting and stopping a vehicle engine by a pair of single channel radio transceivers. An engine running detector senses the started or stopped condition of the vehicle engine and controls a trigger gate so that, when a signal is received, the vehicle engine is stopped if running and started if stopped. Prior to the cranking of the vehicle engine, a throttle actuator fully opens the vehicle throttle to permit the carburetor choke and a fast idle cam to be positioned for starting and accelerator pump shot to be ejected. A microswitch, which is responsive to the return of the throttle to a closed position, senses the failure of the throttle to return to its closed position to prevent the vehicle from being started when the throttle is stuck. In addition, an input override circuit prevents a signal from starting the vehicle engine during the time period when the vehicle engine is being stopped so as to prevent the clashing of the starter gears.

United States Patent Avdenko et a1.

REMOTE ENGINE START AND STOP SYSTEM Inventors: Anatol Avdenko, Rochester; Bruce C. Er-

way, Honeoye Falls, both of NY.

General Motors Corporation, Detroit, Mich.

Filed: June 1, 1970 Appl. No.: 41,872

Assignee:

References Cited UNITED STATES PATENTS 7/1969 Hawthorne ..180/114 X 7/1965 Wolfe, Sr ...343/225 X 9/1962 Fuciarelli ..290/37 A 5/1959 Williams ..290/37 A [151 3,657,720 [451 Apr. 18, 1972 Primary Examiner-John W. Caldwell Assistant Examiner-William M. Wannisky Attorney-Jean L. Carpenter and Paul Fitzpatrick [5 7] ABSTRACT A remote engine start and stop system for remotely starting and stopping a vehicle engine by a pair of single channel radio transceivers. An engine running detector senses the started or stopped condition of the vehicle engine and controls a trigger gate so that, when a signal is received, the vehicle engine is stopped if running and started if stopped. Prior to the cranking of the vehicle engine, a throttle actuator fully opens the vehicle throttle to permit the carburetor choke and a fast idle cam to be positioned for starting and accelerator pump shot to be ejected. A microswitch, which is responsive to the return of the throttle to a closed position, senses the failure of the throttle to return to its closed position to prevent the vehicle from being started when the throttle is stuck. In addition, an input override circuit prevents a signal from starting the vehicle engine during the time period when the vehicle engine is being stopped so as to prevent the clashing of the starter gears.

5 Claims, 7 Drawing Figures STARTER SOLENOID COIL INPUT OVERRIDE CIRCJIT 5 Sheets-Sheet 1 Patented April 18, 1972 Patented April 18, 1972 a Shets-Sheet s IIIII /a0-5 HEATER AND AIR CONDITIONER CONTROLS, ha TO ACCESSORIES g TO IGNITION COIL w I I! /6'3' *I -2 I II MI I #41 I 76 I I M w I I I I I m I I 15% I I I I?! I J L I I INVENTORS fina/o/ AVG/612140 (5 BY fizz/0e C 51:00

A TTORNEY Patented A i-il 18, 1972 3,657,720

5 Sheets-Sheet 4 Patented April 18, 1972 5* Sheets-Sheet 5 R O T A On E N E G If? 50 f r z 220 \{26 H 222 I J g. 7

REMOTE ENGINE START AND STOP SYSTEM This invention relates to a remote engine start and stop system utilizing single channel radio transceivers.

Numerous devices have been proposed for starting a vehicle engine which do 'not require the operator to be within the vehicle. One form of these devices requires an electrical connection between the control station and the vehicle. This requirement limits thephysical location at which the vehicle engine may be remotely controlled. Another form of these devices utilizes a timer such as a clock which initiates the starting of the vehicle engine at a predetermined and set time. This form has the inherent disadvantage of requiring the vehicle operator to ascertain beforehand-the time at which he desires the vehicle to be started. In addition, this form does not provide means for remotely changing the time which was originallyset by the vehicle operator. Yet another form of these devices includes remotely starting a vehicle engine by means of radio receivers and transmitters. This form of controlling a vehicle engine does not have the disadvantages as i mentioned in conjunction with the other forms of vehicle engine control. It is to this form of vehicle engine control that this invention is directed.

Prior systems utilizing radio senders and receivers for controlling the vehicle engine include single channel systems for starting and stopping the vehicle engine and multi-channel systems for providing various functions such as priming the vehicle engine, starting the vehicle engine and periodically pumping the vehicle engine after being started. None of the priorsystems provide for protection against the starting of a vehicle engine in which the throttle is stuck in an open positron.

It is the general object of this invention to provide for a remote engine start and stop system utilizing two single channel transceivers. 7

It is another object of this invention to provide for a remote engine start and stop. system which includes means for preventing the engine from being started when the throttle is stuck in an open position.

These and other objects of this invention are accomplished by generating a start-stop signal in response to a command radio signal. The start-stop signal is coupled to an engine start circuit when the vehicle engine is stopped and is coupled to an engine stop circuit when the'vehicle engine is running. When the signal is coupled to the engine start circuit, a throttle actuator is energized to fully open the vehicle throttle to permit the carburetor choke and the fast idle cam to be positioned for starting and the accelerator pump shot to be ejected. The vehicle throttle is them allowed to return to its closed position to close a switch through which a signal. is sent to the vehicle starter circuit. Failure of the throttle to return to a closed position prevents the signal from being passed through the switch to the starter circuit and starting the vehicle engine while the throttle is stuck in an open position. When the signal is coupled to the engine stop circuit, the vehicle ignition system is de-energized for a specified time duration required to stop the vehicle engine. At the same time the stop circuit prevents another start-stop signal from being generated as a result of a second command radio signal before the vehicle engine has fully stopped.

The invention may be best understood by reference to the following description of a preferred embodiment and the following diagrams in which:

FIG. l is a block diagram of a remote engine start and stop system incorporating the principles of this invention.

FIG. 2 is a block diagram showing the arrangement of FIGS. 3 to 6 inclusive to make a complete detailed circuit diagram of the block diagram of FIG. 1.

FIG. 3 is a schematic drawing of the start-stop pulse generator, the signal received and run indication circuit and the input override circuit of FIG. 1.

FIG. 4 is a schematic drawing of the trigger gate, the throttle actuator timer and the starter time of FIG. 1.

FIG. 5 is a schematic drawing of the start interrupt circuit, the ignition coil supply circuit, the stop timer, the throttle kick timer and the run indication controller of FIG. 1.

FIG. 6 is a schematic drawing tor of FIG. 1.

FIG. 7 is a schematic drawing of the throttle actuator utilized in a preferred embodiment of this invention.

Referring to FIG. 1, a portable remote radio transceiver 10 contains a single channel transmitter 12 and a receiver 14. A vehicle transceiver 16, which may be permanently mounted in the vehicle whose engine is to be remotely controlled, contains a single channel transmitter 18 and a receiver 20. When a start or stop command radio signal is transmitted from the transmitter 12, the radio signal is detected by the receiver 20 which provides an output signal to a start-stop pulse generator 22. From this point, the sequence of events is a function of whether the vehicle engine is started or stopped.

Assuming that the vehicle engine is stopped, the start-stop pulse generator 22 supplies a signal to a signal received and run indication circuit 24 which energizes the transmitter 18. The transmitter 18 beams a radio signal to the receiver 14 of the transceiver 10 which in turn gives an audio or visual indiof the engine running deteccation that the transmitted radio signal has been received by the transceiver 16. In addition, the 22 supplies a pulse to a trigger gate 26 which senses a stopped condition of the vehicle engine as detected by an engine running detector 28 and couples the output of the start-stop pulse generator 22 to a throttle actuator timer 30.

The throttle actuator timer 30 supplies a signal to a throttle actuator 32 for a specified time to fully open the vehicle throttle to permit the carburetor choke and the fast idle cam to be positioned for starting and the accelerator pump shot to be ejected. After the specified time, the throttle is permitted to return to its closed position. When the throttle returns to its closed position the throttle actuator 32 enables the throttle actuator timer 30 to supply a pulse to a starter timer 34.

The starter timer 34 energizes a vehicle starter solenoid coil 36 through a vehicle transmission neutral and park switch 38. If the vehicle transmission has not been placed in neutral or park position, the starter solenoid coil 36 cannot be energized by the starter timer 34. When it is desired to start the vehicle engine manually, the starter solenoid coil 36 is energized start-stop pulse generator through the neutral switch 38 by the conventional ignition switch 40. During the period of time that the starter solenoid coil 36 is energized by the starter timer 34, an ignition coil 42 is energized from the starter solenoid (not shown).

When the vehicle engine has started, the engine running detector 28 detects when the engine is turning over at a higher RPM than the maximum possible cranking RPM by monitoring the output of the vehicle generator 44. When the vehicle engine has started, as detected by the engine running detector 28, an ignition coil supply circuit 46 is energized through the neutral and park switch 38 to supply energy to the ignition coil 42 to maintain the vehicle engine running. When the neutral and park switch 38 is opened, the ignition coil supply circuit 46 is prevented from supplying energy to the ignition coil 42. Therefore, if the vehicle transmission is taken out of the neutral or park position after the vehicle engine has been remotely started, the vehicle engine will stop unless the key has been inserted and turned to on" position. In addition, after the engine running detector 28 has detected a vehicle engine running condition, a start interrupt circuit 48 is energized to reset the starter timer 34 so as to de-energize the starter solenoid coil 36.

Immediately after the vehicle engine has started, the engine running detector 28 energizes a throttle actuator timer control 50 and a throttle kick timer 52. The throttle actuator timer control 50 and the throttle kick timer 52 control the throttle actuator timer 30 so as to periodically partially open the vehicle throttle after the engine is running to gradually step the carburetor throttle off of the high idle cam as the engine warms up. The engine running detector 28 also supplies a signal to the starter timer 34 to prevent the starter timer from being energized by the throttle actuator timer 30 as the vehicle throttle is periodically opened and closed.

A run indication controller 54 receives a signal from the engine running detector 28 and periodically energizes the signal received and run indication circuit 24 which in turn periodically energizes the transmitter 18 to send a pulsing radio signal to the receiver 14 of the transceiver 10 which gives a periodic indication that the vehicle engine is started. The output of the engine running detector 28 may also be utilized to energize the vehicle heater and air conditioner control 56.

If the vehicle engine is started and a command radio signal is transmitted by the transmitter 12 and detected by the receiver 20, the trigger gate 26 senses the started condition of the engine as determined by the output of the engine running detector 28 and couples the output of the start-stop pulse generator 22 to a stop timer 58. The stop timer 58 de-energizes the ignition coil supply circuit 46 and consequently the ignition coil 42 for a specified time duration required for the vehicle engine to fully stop. Simultaneously, the stop timer 58 supplies a signal to an input override circuit 60 which prevents the start-stop pulse generator 22 from supplying another pulse to the trigger gate 26 in. response to a command radio signal rec'eivedby the receiver 20. This is a safety feature to prevent an attempt to start the vehicle engine prior to the vehicle engine being fully stopped to prevent a clashing of the starter gear by preventing the starter solenoid coil 36 from being energized before the vehicle engine is fully stopped.

Reference will now be made to the FIGS. 3, 4, and 6 arranged as shown in FIG. 2 to complete a circuit diagram of the block diagram in FIG. 1.

Referring to FIGS. 3 and 4, the vehicle transceiver 16 receives power from a vehicle battery 62 through a normally closed relay contact 398-1, the vehicle transmission neutral and park switch 38, a normally closed relay contact 398-2, a line 66 and a current limiting resistor 68. A Zener diode 70 provides a regulated voltage input to the transceiver 16.

Referring to FIG. 3, the start-stop pulse generator 22 is comprised of a relay coil 72, a normally open relay contact 72-1 which is controlled by the relay coil 72, resistors 76, 78

' and 80, a capacitor 82, and a transistor 84 connected as shown. When the receiver 20 receives a command radio signal from the transmitter 12, an output is generated to energize the relay coil 72. The relay contact 72-1 is closed to complete a circuit from a regulated power supply 86 in FIG. 4 through a line 87, resistor 76, the relay contact 72-1, the capacitor 82 and the resistor 78 to momentarily bias the transistor 84 into conduction. The time during which the transistor 84 is'con- I ducting is determined by the time constant of the series circuit including the resistor 76, the resistor 78 and the capacitor 82.

During this time, an output pulse is generated across the resistor8 0.

The output pulse from the start-stop pulse generator 22 is coupledthrough a diode 91 to the signal received and run indication circuit 24 which includes a single shot multi-vibrator 88. The output pulse triggers the single shot multi-vibrator 88 which is comprised of a transistor 89, a transistor 90, capacitors 92 and 94, a diode 96, and resistors 98, 100, 102, 104, 106 and 108 connected as shown. The time constant of the single shot multi-vibrator 88 is determined by the time constant of the capacitor 94 and the resistor 108. When triggered, the single shot multi-vibrator 88 biases a transistor 110 into conduction for a time period determined by the time constant of the capacitor 94 and the resistor 108. During this time,

power is supplied through a diode 112 to energize the transmitter 18 so as to transmit a radio signal to the receiver 14 which provides an indication that the transmitted signal from the transmitter 12 has been received by the transceiver 16. The signal received and run indication circuit 24 receives its power from the regulated power supply 86 in FIG. 3 through the line 87 in FIG. 5.

In addition to being coupled to the signal received and run indication circuit 24, the output pulse of the start-stop pulse generator 22 is coupled to the trigger gate 26 in FIG. 3

through a line 113 which is comprised of thediodes 114 and 116, the capacitors 118 and 120, and resistors 122 and 124 connected as shown. The trigger gate 26 is controlled by the engine running detector 28 in FIG. 6.

Referring to FIG. 6, the engine running detector 28 is comprised of the transistors 126, 128, 130, 132, 134 and 136, the resistors 138, 140, 142, 144,146, 148, 150, 152, 154, 156 and 158, the capacitors 159 and 161 and a diode 162 connected as at a higher RPM than the maximum possible cranking RPM.

When this condition exists, the single shot multi-vibrator comprised of the transistors 128 and 130 fires to turn on the transistor 132 and the Darlington amplifier comprised of the transistors 134 and 136 to energize a relay coil 160. The relay coil controls the position of the normally open relay contacts 160-2 in FIG. 4 and 160-3 in FIG. 5 and the normally closed relay contacts 160-4, 160-5 and 160-6 in FIG. 4, and 160-7 in FIG. 5.

Referring to FIG. 4 and assuming the vehicle engine is stopped, the relay coil 160 of FIG. 6 is de-energized and the contact 160-4 in the starter 34 of FIG. 4 is closed and the contact 160-3 in the ignition coil supply circuit 46 of FIG. 5 is open. Power is supplied through the normally closed relay contact 160-4 through the resistor 124 to charge the capacitor 120. When this condition exists, the output pulse from the start-stop pulse generator 22 of FIG. 3 supplied through the line 113 is prevented from passing through the diode 116 which is back biased by the charge on thecapacitor 120. The output pulse of the start-stop pulse generator 22 is coupled through the diode 114 and the capacitor 118 of the trigger gate 26 to the throttle actuator timer 30.

The throttle actuator timer 30 is comprised of the transistors 174, 176, 178, and 182, the resistors 184, 186, 188, 190, 192, 194, 195, 196, 198, 200 and 202, the capacitors 204 and 206, and the diodes 208 and 210 connected as shown. The transistors 174 and 176 and their associated circuitry form a single shot multi-vibrator 211 whoseoutput turns on the transistor 178 and a Darlington amplifier 212 comprised of the transistors 180 and 182 for a time period determined by the time constant of the resistors 184 and 186 in conjunction with the capacitor 204. The output of the Darlington amplifier 212 energizes a throttle actuator solenoid 213 through the contacts 398-1 and 398-2 and the neutral and park switch 38 for the period of time determined by the single shot multi-v'ibrator 211. The throttle actuator timer receives operating power from the regulated power supply 86.

Referring to FIG. 7, the throttle actuator 32 is comprised of a vacuum reservoir 218 which receives a vacuum supply from the vehicle manifold (not shown) through a conduit 220 and a check valve 222. The vacuum reservoir 218 is sealed so as to retain the vacuum created by the vehicle manifold for a long period of time. Vacuum from the vacuum reservoir 218 is supplied to a chamber 224 through a conduit 226. The chamber 224 also has an atmospheric air input through a conduit 228. The chamber 224 is pneumatically connected to a throttle actuator cylinder 230 by means of a conduit 231. The throttle actuator cylinder 230 contains a piston 232 which is connected to a throttle actuator 234 of a conventional vehicle carburetor 236 by means of a linkage 238. The throttle actuator 234 is normally biased to a closed position as shown to move the piston 232 of the throttle actuator cylinder 230 against a microswitch 240. A valve member 242 within the chamber 224 is normally biased by a spring 244 to seal the conduit 226 to prevent the admission of vacuum from the vacuum reservoir 218. The throttle actuator solenoid 213, which is energized as previously described with reference to FIG. 4, biases the valve member 242 to close the atmospheric air input from the conduit 228 and open the vacuum input through the conduit' 226 from the vacuum reservoir 218. Vacuum input to the chamber 224 is transferred through the conduit 231 to the throttle actuator cylinder 230 to move the piston 232 against the return force of the throttle actuator 234 to open the vehicle throttle, (not shown). The time which the throttle actuator solenoid 213 is energized controls the distance through which the piston 232 moves in the throttle actuator cylinder 230. The time constant of the single shot multi-vibrator 211 of FIG. 4, as determined by the resistors 184, 186 and the capacitor 204 is such that the piston 232 moves to fully open the vehicle throttle 234 to permit the carburetor choke and the fast idle cam to be positioned for starting and the accelerator pump shot to be ejected. Referring again to FIGS. 4 and 7, during the time interval that the throttle actuator solenoid 213 is energized, the microswitch 240 is open and the capacitor 206 is charged through the series combination of the resistor 188, the diode 210 and the resistor 202. After the specified time duration, the throttle actuator solenoid 213 is de-energized to permit the valve member 242 to be returned by the spring 244 to close the vacuum input and to admit atmospheric air into the chamber 224 and the throttle actuator cylinder 230. The carburetor throttle will return to its closed position to position the piston 232 against the microswitch 240. The microswitch 240 is closed by the piston 232 to provide a discharge path for the capacitor 206 to supply a pulse to the starter timer 34. As can be seen, if the vehicle throttle is stuck to an open position, the piston 232 is not returned against the microswitch 240 with the result that the microswitch 240 remains open to prevent a pulse from being supplied to the starter timer circuit 34.

Referring to FIG. 4, the starter timer 34 is comprised of the transistors 246, 248, 250, 252 and 254, the resistors 256, 260, 262, 264, 266, 268, 270, 272, 274, 276 and 278, the diodes 280, 282, 284 and 286, the capacitors 288, 290 and 292, the hood switch 294, and the starter relay coil 296 connected as shown. The hood switch 294 is provided to prevent the accidental starting of the vehicle engine while the hood is open. The starter relay coil 296 controls a normally open contact 296-1. When the microswitch 240 is closed by the vehicle throttle returning to its closed position, the discharge pulse from the capacitor 206 is coupled to a single shot multi-vibrator 303 comprised of the transistors 246 and 248 and their associated circuitry through the diode 280. The time duration that the single shot multi-vibrator 303 is triggered is determined by the time constant of the resistor 266 and the capacitor 290. During this time period, the transistor 252 is turned on to supply a current pulse through the hood switch 294 to turn on the starter driver transistor 254. When the transistor 254 is turned on, the starter relay coil 296 is energized through the relay contacts 398-1 and 160-6 and the neutral and park switch 38 to close the normally open relay contact 296-1 to energize the starter solenoid 36. During the time period which the single shot multi-vibrator 303 is triggered, the starter motor is energized to crank the vehicle engine. If the vehicle engine does not start during this time period, another command signal transmitted by the transmitter 12 of FIG. 3 will be required to initiate another vehicle start signal. The starter timer 34 receives its power from the regulated power supply 86 as shown.

If the vehicle engine starts while the starter solenoid coil 36 is energized, the relay coil 160 is energized by the engine running detector 28 of FIG. 6 to open the relay contacts 160-4 and 160-6. When the relay contact 160-6 opens, the starter relay coil 296 is de-energized to open the relay contact 296-l to de-energize the starter solenoid coil 36 to stop the cranking of the vehicle engine by the starter motor. In addition, when the relay contact 160-4 closes, the start interrupt circuit 48 of FIG. 5, which is comprised of the transistor 308, the resistors 310, 312 and 314, and the diodes 316 and 318 is energized through the line 319 to turn on the transistor 308 to supply a pulse through a line 320 to cause the single shot multi-vibrator 303 in the starter timer 34 to be reset to turn off the starter relay coil driver transistor 254. As can be seen, the starter relay coil driver transistor 254 is energized through the hood switch 294 so as to prevent the accidental starting of the vehicle engine while the hood of the vehicle is open which indicates that the vehicle engine is being worked on.

While the starter solenoid coil 36 is energized, the ignition coil (not shown) is energized from the starter solenoid in the conventional manner.

Referring to FIG. 5, when the vehicle engine has started, the relay contact -3 in the ignition coil supply circuit 46 is closed by the relay coil 160 of FIG. 6 to energize the ignition coil supply circuit 46 which is comprised of the transistors 321 and 322 arranged in a Darlington amplifier configuration and the resistors 324, 326, 328 and 330 connected as shown. When the relay contact 160-3 is closed, the Darlington amplifier is turned on to energize an ignition relay coil 332 through the normally closed relay contact 398-2 in FIG. 4 and a line 333 which closes a relay contact 332-l in FIG. 4 to energize the ignition coil and maintain the ignition coil energized when the engine has started. Power for the ignition coil supply circuit 46 is obtained from the regulated power supply 86 through the line 163.

The throttle kick timer 52 is comprised of a unijunction transistor 336, the resistors 338, 340 and 342 and a capacitor 344 connected as shown.

The run indication controller 54 is comprised of a unijunction transistor 346, the resistors 348, 350 and 351 and capacitor 352 connected as shown.

Each unijunction transistor 336 and 346 is connected with its respective circuit elements in a relaxation oscillator configuration with power being supplied from the regulated power supply 86 through the line 163. The frequency of oscillation of the throttle kick timer 52 is determined by the time constant of the resistor 338 and the capacitor 344 and the frequency of oscillation of the run indication controller 54 is determined by the time constant of the resistor 348 and the capacitor 352.

Prior to the vehicle engine being started a clamping circuit comprised of the normally closed relay contact 160-7, the resistors 353 and 354 and the diodes 356, 358, 360 and 362 causes the capacitors 344 and 352 to be charged near the voltage required to fire the unijunction transistors 336 and 346. When the vehicle engine starts, the nonnally closed relay contact 160-7 in the throttle kick timer 52 and the normally open relay contact 160-3 in the ignition coil supply circuit 46 are respectively opened and closed by the relay coil 160 in the engine running detector 28 of FIG. 5 to remove the clamp and to back bias the diodes 358 and 362 through a diode 363 with the result that each unijunction transistor 336 and 346 is triggered immediately after the vehicle engine has started. The output of the throttle kick timer 52 is taken across the resistor 342 and supplied to the throttle actuator timer 30 of FIG. 4 through a line 404 to trigger the single shot multi-vibrator 211. The time constant of the single shot multi-vibration 211 which was previously determined by the resistors 184 and 186 and the capacitor 204 is changed upon the starting of the vehicle engine by the closure of the relay contact 160-2 by the relay coil 160 in the engine running detector 28 of FIG. 6 to short the resistor 184 so that the time constant is then determined solely by the resistor 186 and the capacitor 204. This time constant is less than the time constant of the single multivibrator shot 211 prior to the vehicle engine starting with the result that the Darlington amplifier 212 comprised of the transistors and 182 are turned on for a lesser time to partially open the vehicle throttle. The throttle is therefore periodically partially opened by the throttle actuator timer 30 as controlled by the throttle kick timer 52 as long as the vehicle engine is running.

The output of the run indication controller 54 is taken across the resistor 350 to periodically supply a pulse to the signal received and run indication circuit 24 of FIG. 3 through a line 364 and a diode 356 so as to periodically trigger the single shot multi-vibrator 88 to cause the transmitter 18 to periodically transmit a radio signal to the receiver 14 to indicate that the vehicle engine has started and is running.

When the vehicle engine has started, the relay contact 160-4 in the starter timer 34 is opened and the capacitor 120 of the trigger gate 26 discharges through the resistor 124 to remove the back bias on the diode 116. In addition, the relay contact 160-3 in the ignition coil supply circuit 46 is closed to charge the capacitor 118 through the resistor 122 to back bias the diode 114 of the trigger gate 26 and the capacitor 288 of the starter timer 34 is charged through the resistor 256 to back bias the diode 280 to prevent the triggering of the starter timer 34 as the vehicle throttle is periodically opened and closed while the vehicle engine is running as previously described. The resistors 122, 124 and 256 are made large to limit the current pulses therethrough to a small value so as to have no affect on conditions existing in the system at that time.

When it is desired to stop the vehicle, a radio signal is transmitted from the transmitter 12 of the transceiver 10 of FIG. 3 to the transceiver 16 so as to generate a pulse at the output of the start-stop pulse generator 22 which is supplied to the trigger gate 26 of FIG. 4 through the line 113. The diode 114 of the trigger gate 26 is back biased by the charge on the capacitor 118, to prevent the pulse from passing to the throttle actuator timer 30. Since the back bias on the diode 116 which was present when the vehicle was stopped has been removed as the result of the starting of the vehicle engine, the output pulse of the start-stop pulse generator 22 is passed through the diode 116, the capacitor 120 and a line 365 to the stop timer 58 in FIG. which is comprised of the transistors 366 and 367, the resistors 368, 370, 372, 374 and 376, a diode 378 and a capacitor 380 connected as shown. The stop timer receives power from the regulated power supply 86 through the line 163. The transistors 366 and 367 and their associated circuitry are connected in the form of a single shot multi-vibrator 381 having a time constant determined by the resistor 376 and the capacitor 380. The input pulse coupled through the diode 116 and the capacitor 120 in the trigger circuit 26 triggers the single shot multi-vibrator 381 to short the Darlington amplifier comprised of the transistors 320 and 322 of the ignition coil supply circuit 46 through a diode 382 and the transistor 366. The ignition relay coil 332 in the ignition coil supply circuit 46 is therefore de-energized for the time duration that the single shot multi-vibrator 381 is triggered. With the ignition relay coil 332 deenergized, the relay contact 332-1 in FIG. 4 is opened to prevent power from being supplied to the ignition coil-so as to stop the vehicle engine. The time duration which the ignition relay coil 332 is de-energized is of such a length as to allow the vehicle engine to fully stop. In addition, during the time duration that the single shot multi-vibrator 381 is triggered, a pulse is applied through a diode 384 and a line 385 to the input override circuit 60 of FIG. 3 which is comprised of a transistor 386 and the resistor 388 connected as shown. This pulse turns on the transistor 386 to short the input to the transistor 84 of the start-stop pulse generator 22 to prevent a pulse from being generated and supplied to the throttle actuator timer 30 of FIG. 4 through the diode 114 and the capacitor 118 of the trigger circuit 26 until the vehicle engine has fully stopped. An attempt to start the vehicle engine will therefore, be ineffective while the vehicle engine is in the process of stopping.

The regulated power supply 86 of FIG. 4 is comprised of a current limiting resistor 392 and a Zener diode 393 connected as shown. The input is received from the battery 62 and the outputis taken across the Zener diode 394.

Referring to FIG. 4, the vehicle heater and air conditioner controls 56 may be set to come on automatically through the normally open contact l60-5 when the vehicle engine is started remotely and the contact 160-5 is closed by the engine running relay coil 160 in the engine running detector 28 of FIG. 6.

The vehicle ignition switch 40 has an accessory position contact 394, an ignition position contact 395 and a start position contact 396 connected as shown. When an ignition key is inserted into the ignition switch 40 and turned to the accessory position, the accessory position contact 394 is closed to energize an accessory relay coil 398 which opens the relay contacts 398-1 and 398-2. The power path from the battery 62 to the ignition coil is therefore opened to de-energize the ignition coil to stop the vehicle engine if previously started. When the key is turned to the start position, the start position contact 396 is closed to turn on the transistor 254 of the starter timer 34 through a resistor 402 which energizes the starter relay coil 296 to close the relay contact 296-1. The starter solenoid coil 36 is therefore energized for as long as the start position contact is maintained closed. When the ignition key is returned to the ignition position, both the ignition position contact 395 and the accessory position contact 394 are closed to supply power to the ignition coil and to energize the accessory relay coil 398 to open the relay contacts 398-1 and 398-2. As can be seen, placing the ignition switch 40 in either the accessory position or ignition position disables the remote start-stop circuitry by the opening of the relay contact 398-2 to deenergize the transceiver 16 of FIG. 3. In addition, to drive the vehicle after its engine has been started remotely, the operator must place the ignition switch 40 in the ignition position so as to bypass the relay contact 398-1 and the neutral and park switch 38 which will de-energize the ignition coil upon the transmission being taken out of neutral position.

No particular description of the transceivers l0 and 16 has been shown since many types of such transceivers are available in such fomrs as walkie-talkies or model craft controls.

What has been described is a remote engine start and stop circuit in which the engine is started and stopped by a pair of single channel transceivers. The system protects against the possibility of a stuck throttle by preventing the engine from being remotely started in such a contingency. The system also protects against the accidental starting of the engine while the engine is in the process of stopping to prevent the clashing of the starter motor gears. In addition, the foregoing remote start and stop system in no way interferes with the manual starting or stopping of the engine while yet having the ability to remotely start and stop the vehicle engine upon command.

We claim:

1. An apparatus for remotely starting a vehicle engine hav-' ing a throttle biased to a closed position and a choke and for preventing the accidental racing of the engine when the throttle is stuck in an open position comprising, in combination, means remote from the vehicle for generating the engine start signal; means responsive to the engine start signal and coupled to the throttle for fully opening the throttle to set the choke and releasing the throttle; circuit means for starting the vehicle engine when said circuit means is energized; and switch means coupled to the circuit means and responsive to throttle position for energizing the circuit means when the throttle returns to a closed position for starting the vehicle engine, wherein the failure of the throttle to return to a closed position prevents the energization of the circuit means and therefore the starting of the vehicle engine.

2. An apparatus for remotely starting a vehicle engine having a throttle biased to a closed position and a choke, comprising a radio sender for generating and sending an engine start signal; a radio receiver within the vehicle and responsive to the engine start signal for generating an output signal; means coupled to the radio receiver and responsive to the output signal for fully opening the throttle to set the choke and releasing the throttle, said means including-a vacuum reservoir, a pneumatic motor coupled to the throttle and responsive to the admission of vacuum to open the throttle, timing means, and valve means responsive to the timing means for supplying vacuum from the vacuum reservoir to the pneumatic motor to cause the'pneumatic motor to open the throttle and responsive to the timing means for releasing the vacuum in the pneumatic motor to release the throttle; and means responsive to the return of the throttle to a closed position for starting the vehicle engine, wherein the failure of the throttle to return to a closed position prevents the starting of the vehicle engine.

3. The apparatus as claimed in claim 2 wherein the means responsive to the return of the throttle to a closed position for starting the vehicle engine includes a microswitch actuated by the return of the throttle to a closed position for starting the engine.

4. An apparatus for remotely starting and stopping a vehicle engine comprising a radio sender for generating and sending a command signal; a radio receiver within the vehicle and responsive to the command signal for generating an output signal; engine starting means; engine stopping means; and means for sensing the started or stopped condition of the engine and responsive thereto for coupling the the output signal to the engine starting means when the engine is stopped and to the engine stopping means when the engine is started, the means for sensing the started or stopped condition of the engine and responsive thereto for coupling the output signal to the engine starting means when the engine is stopped and to the engine stopping means when the engine is started including first one-way current passing means for supplying the output signal to the engine starting means, second one-way current passing means for supplying the output signal to the engine stopping means, means for back biasing the first one-way current passing means when the engine is started to prevent the output signal from passing to the engine starting means, and means for back biasing the second one-way current passing means when the engine is stopped to prevent the output signal from passing to the engine stopping means.

5. An apparatus for remotely starting and stopping a vehicle engine having a throttle, choke and ignition system comprising a radio sender for generating and sending a command signal; a radio receiver within the vehicle and responsive to the command signal for generating an output signal; engine starting means; means for sensing a stopped condition of the engine and responsive thereto for coupling the output signal to the engine starting means, the engine starting means including means responsive to the output signal for fully opening the throttle to set the choke and releasing the throttle means responsive to the return of the throttle to a closed position for starting the vehicle engine; engine stopping means; and means for sensing a started condition of the engine and responsive thereto for coupling the output signal to the engine stopping means when the engine is started, the engine stopping means including a timing means for de-energizing the ignition system for a specified time duration required to stop the vehicle engine and for preventing the energization of the starter solenoid for the specified time duration to prevent energization of the starter while the vehicle engine is running. 

1. An apparatus for remotely starting a vehicle engine having a throttle biased to a closed position and a choke and for preventing the accidental racing of the engine when the throttle is stuck in an open position comprising, in combination, means remote from the vehicle for generating the engine start signal; means responsive to the engine start signal and coupled to the throttle for fully opening the throttle to set the choke and releasing the throttle; circuit means for starting the vehicle engine when said circuit means is energized; and switch means coupled to the circuit means and responsive to throttle position for energizing the circuit means when the throttle returns to a closed position for starting the vehicle engine, wherein the failure of the throttle to return to a closed position prevents the energization of the circuit means and therefore the starting of the vehicle engine.
 2. An apparatus for remotely starting a vehicle engine having a throttle biased to a closed position and a choke, comprising a radio sender for generating and sending an engine start signal; a radio receiver within the vehicle and responsive to the engine start signal for generating an output signal; means coupled to the radio receiver and responsive to the output signal for fully opening the throttle to set the choke and releasing the throttle, said means including a vacuum reservoir, a pneumatic motor coupled to the throttle and responsive to the admission of vacuum to open the throttle, timing means, and valve means responsive to the timing means for supplying vacuum from the vacuum reservoir to the pneumAtic motor to cause the pneumatic motor to open the throttle and responsive to the timing means for releasing the vacuum in the pneumatic motor to release the throttle; and means responsive to the return of the throttle to a closed position for starting the vehicle engine, wherein the failure of the throttle to return to a closed position prevents the starting of the vehicle engine.
 3. The apparatus as claimed in claim 2 wherein the means responsive to the return of the throttle to a closed position for starting the vehicle engine includes a microswitch actuated by the return of the throttle to a closed position for starting the engine.
 4. An apparatus for remotely starting and stopping a vehicle engine comprising a radio sender for generating and sending a command signal; a radio receiver within the vehicle and responsive to the command signal for generating an output signal; engine starting means; engine stopping means; and means for sensing the started or stopped condition of the engine and responsive thereto for coupling the output signal to the engine starting means when the engine is stopped and to the engine stopping means when the engine is started, the means for sensing the started or stopped condition of the engine and responsive thereto for coupling the output signal to the engine starting means when the engine is stopped and to the engine stopping means when the engine is started including first one-way current passing means for supplying the output signal to the engine starting means, second one-way current passing means for supplying the output signal to the engine stopping means, means for back biasing the first one-way current passing means when the engine is started to prevent the output signal from passing to the engine starting means, and means for back biasing the second one-way current passing means when the engine is stopped to prevent the output signal from passing to the engine stopping means.
 5. An apparatus for remotely starting and stopping a vehicle engine having a throttle, choke and ignition system comprising a radio sender for generating and sending a command signal; a radio receiver within the vehicle and responsive to the command signal for generating an output signal; engine starting means; means for sensing a stopped condition of the engine and responsive thereto for coupling the output signal to the engine starting means, the engine starting means including means responsive to the output signal for fully opening the throttle to set the choke and releasing the throttle and means responsive to the return of the throttle to a closed position for starting the vehicle engine; engine stopping means; and means for sensing a started condition of the engine and responsive thereto for coupling the output signal to the engine stopping means when the engine is started, the engine stopping means including timing means for de-energizing the ignition system for a specified time duration required to stop the vehicle engine and for preventing the energization of the starter solenoid for the specified time duration to prevent energization of the starter while the vehicle engine is running. 